In the early days of ordinary language philosophy at Oxford University, and perhaps inspired by the need for "usage examples" to define a term in a dictionary (consider the great OED), some philosophers called for "paradigm cases" to establish the meaning of a word. Understanding a concept, doing "conceptual analysis," then became simply a matter of finding an appropriate paradigm case.

Very early in the development of such paradigm case arguments, "free will" became a paradigm of analysis by finding a paradigm case. Antony Flew found one in the case of a man who marries the girl he wants to marry, under no social pressure.

The "pressure" reference is, of course, to the absence of any external constraints or compulsions that might limit his "freedom of action" or "compatibilist free will."

Flew says

"The clue to the whole business now seems to lie in
mastering what has recently been usefully named, The Argument of the
Paradigm Case.69 Crudely: if there is any word the meaning of which can
be taught by reference to paradigm cases, then no argument whatever
could ever prove that there are no cases whatever of whatever it is. Thus,
since the meaning of 'of his own freewill' can be taught by reference to
such paradigm cases as that in which a man, under no social pressure,
marries the girl he wants to marry (how else could it be taught ?): it cannot
be right, on any grounds whatsoever, to say that no one ever acts of his own
freewill. For cases such as the paradigm, which must occur if the word is
ever to be thus explained (and which certainly do in fact occur), are not
in that case specimens which might have been wrongly identified: to the
extent that the meaning of the expression is given in terms of them they
are, by definition, what 'acting of one's own freewill' is. As Runyon would
say: If this isn't an x, it will at least (do till an x comes along. A moment's
reflexion will show that analogous arguments can be deployed against
many philosophical paradoxes.

"What such arguments by themselves will certainly not do is to establish
any matter of value, moral or otherwise: and almost every one who has
used them, certainly the present writer, must plead guilty to having from
time to time failed to see this. For one cannot derive any sort of value
proposition: from either a factual proposition about what people value: or
from definitions however disguised of the value terms which people as a
matter of fact employ."

The next year Arthur Danto wrote an article, "The Paradigm Case Argument and the Free-Will Problem." He doubted that a paradigm-case argument was useful for the "real problem of free will."

I wish to show that the sort of argument I have quoted does not in fact close the books even on the ancient issue. And I wish to show that ordinary language so construed is simply
irrelevant to the celebrated problem of the freedom of the will.

Danto nicely points out that what the (comaptibilist and determinist) philosophers of his time considered the "free-will problem" was not the ordinary language use in this paradigm case.

The occasions on which we might use the
expression in ordinary life are really rather
special. There is, of course, the reproachful
use: Smith has botched his marriage and
cries on our shoulder, so we say "Well, you
married of your own free-will." We would
not say this were we sympathetic with
Smith, or felt his problem deeply, or were
being paid to listen to him, or blamed his
wife. Mainly, however, we use the expression
only when someone else has said, or
thought, that somebody was forced to do
something against his will. "He did it of his
own free-will" then serves to deny such an
assertion.

It is a characteristic (and perhaps a crucial)
difference between ordinary and philosophical
denials of free-will that willingness
is not a component of the latter. The
determinist is surely not arguing the patently
false proposition that we always act
unwillingly, contrary to our will. But that,
I think, is nearly always what we mean in
ordinary life when we say that someone did
not act of his own free-will. We mean he
was forced to do it. Furthermore, we never
say, apropos of nothing, that someone did
something of his own free-will. Indeed, were
someone to tell me that Smith married and
add that he did so of his own free-will, I
should wonder what he was insisting upon.
And I would gather that there was more to
the story than I had been aware of.
Now if I am correct in all this, then, I
think, even if determinism came to be universally
accepted, it would leave this part
of ordinary language quite unmodified. For
people would still have inclinations, would
still sometimes be forced to act against
those inclinations, would very likely still
seek extenuation, etc. Or they would sometimes
be released from certain pressures,
restrictions, and obligations. So we should
still require the expressions we now employ,
e.g., "He did it of his own free-will" or "He
is free" (i.e., "no longer in conference,"
"no longer engaged to the girl from Vassar,"
"has broken the habit," "is out of
jail").

Someone might of course complain, once
determinism were universally accepted, that
these expressions smack of an old, wrong
view of things, that new expressions ought
to be found. But what would be the gain?
The distinctions would still need somehow
to be made. And the point is, the expression
"of his own free-will" is used simply to make these distinctions now.